The problem with Public land is the diminishing amout of it which is reasonably accessible. Out here in the west, land managers seem to enjoy decommissioning public access to "preserve" the land. Areas once accessible by vehicle are often made inaccessible by digging out roads leading into the area. Mind you, I like closed and gated areas, but I am talking about managers closing access to vast areas making entry in by foot the only option. Who has access now? Only a limited amount of folks who are in great or excellent shape. My dad cannot access huge chunks of public land now, areas he had access to for decades. Now the area is only open to a select few, or criminals willing to drive around gates and tanktraps.
Also, jerks who dump trash in the woods are also responsible for gates. Now, they just dump their crap closer to the highway, and the gate stays. Trash still happens, gates stay up, old timer hunters get locked out.
Private land companies are continually closing access to their lands causing more folks to flock to public land. Add all these together and you have a bad situation continually worsening.